package com.itheima.reggie.controller;

import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.UUID;

@Slf4j
@RestController
@RequestMapping("/common")
public class CommonController {

    //在yml文件中配置路径
    @Value("${reggie.path}")
    private String basePath;

    /**
     * 文件上传
     * @param file
     * @return
     */
    @PostMapping("/upload")
    public R<String> upload(MultipartFile file){
        //file是一个临时文件,需要转到指定存储位置,否则本次请求完成后文件会删除
        log.info("file {}",file.toString());
        //原始文件名
        String originalFilename = file.getOriginalFilename();
        String suffix = null;
        if (originalFilename != null) {
            suffix = originalFilename.substring(originalFilename.lastIndexOf("."));
        }
        //防止文件名重复,使用uuid
        String filename = UUID.randomUUID().toString() + suffix;
        //创建一个目录对象
        File dir = new File(basePath);
        //判断当前目录是否存在
        if(!dir.exists()){
            dir.mkdirs();
        }
        try {
            //将临时文件转存到本地
            file.transferTo(new File(basePath+filename));
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        return R.success(filename);
    }

    @GetMapping("/download")
    public void download(String name, HttpServletResponse response) {
        FileInputStream fileInputStream=null;
        ServletOutputStream outputStream=null;
        //输入流,通过输入流读取文件内容
        try {
            fileInputStream = new FileInputStream(new File(basePath+name));

        //输出流,通过输出流将文件写回浏览器,在浏览器展示图片
            outputStream = response.getOutputStream();

            response.setContentType("image/jpg");

            int len = 0;
            byte[] bytes = new byte[1024];
            while((len =fileInputStream.read(bytes)) !=-1){
                outputStream.write(bytes, 0, len);
                outputStream.flush();
            }
            outputStream.close();
            fileInputStream.close();

        } catch (IOException e) {
            throw new RuntimeException(e);
        }


    }
}
